The present invention generally relates to a vehicle parking brake. More particularly, the present invention pertains to a foot-operated parking brake control apparatus for vehicles that permits the parking brake to be released by performing the same operation as that performed to effect activation of the parking brake.
A known vehicular foot-operated parking brake control apparatus is disclosed in Japanese Patent Publication No. 2967406. In this apparatus, a pawl for locking a pedal arm by engagement with a plurality of ratchet teeth provided on the pedal arm is rotatably supported on a bracket by a pin so as to be able to slide a predetermined amount in the rotational direction of the pedal arm. A release lever which is adapted to engage the pawl is rotatably supported on the bracket by a pin. A spring is disposed between the pawl and the release lever and the urging direction of the spring against the pawl and the release lever is changed in response to the rotation of the pedal arm.
That is, when the parking brake is not operated, the spring urges the pawl so that the pawl engages the ratchet teeth and simultaneously the spring urges the release lever so that the release lever is separated from the ratchet teeth. When the pedal is depressed and the pedal arm is rotated, the pedal is prevented from returning by the engagement between the pawl and the ratchet teeth and the operation of the parking brake is maintained. At this time, when the depressing force is removed, the pawl slides with a predetermined amount toward the returning side of the pedal and the release lever is rotated close to the ratchet teeth. Thereby, the urging direction of the spring is changed and the spring urges the pawl to separate from the ratchet teeth. Simultaneously, the spring urges the release lever close to the ratchet teeth. In this operating condition of the parking brake, when the pedal is depressed and the pedal arm is rotated, the engagement between the pawl and the ratchet teeth is released and the pawl is rotated to separate from the ratchet teeth. Thereby, the return of the pedal arm is allowed and the operation of the parking brake is released.
In the above-described apparatus, however, because the ratchet teeth are provided on the pedal arm, and the pawl and the release lever are mounted on the bracket, the size of the bracket is increased. As a result, the size of the overall parking brake control apparatus increases and a large space is required for mounting the parking brake control apparatus. This problem becomes more significant if the distance between the arc of the ratchet teeth and the rotational axis of the pedal arm is increased for lessening the stroke loss due to the return of the pedal arm when the depressing force is removed after operating the parking brake.
A need thus exists for an improved vehicular foot-operated parking brake control apparatus which is not as susceptible to the drawbacks mentioned above.
In light of the foregoing, the vehicular foot-operated parking brake control apparatus according to the present invention includes a mounting bracket adapted to be fixed to the vehicle body, a pedal arm rotatably mounted on the bracket for rotation about a rotational axis and being connected to a parking brake control cable, a plurality of ratchet teeth provided on the bracket along an arc disposed about the rotational axis of the pedal arm, and a pawl rotatably mounted on the pedal arm for rotation about a rotational axis between a first rotational position in which the pawl is engaged with one of the ratchet teeth and a second rotational position in which the pawl is disengaged from the ratchet teeth. The rotational axis of the pawl is generally parallel to the rotational axis of the pedal arm, and the pawl is slidably mounted on the pedal arm in the rotational direction of the pedal arm to slide between a first slide position and a second slide position. In addition, a release lever is rotatably mounted on the pedal arm for rotating about a rotational axis that is generally parallel to the rotational axis of the pedal arm to turn between a release rotational position and a non-release rotational position. A spring having a first end connected to the pawl and a second end connected to the release lever imparts a spring force that constantly urges the pawl to slide towards the first slide position. The spring urges the release lever to stay in the non-release rotational position and urges the pawl to turn towards the first rotational position when the release lever is in the non-release position, and urges the release lever to stay in the release rotational position and urges the pawl to turn towards the second rotational position when the release lever is in the release rotational position. A first cooperating mechanism is provided between the pawl and the release lever for turning the release lever from the non-release rotational position to the release rotational position when the pawl is moved from the first slide position to the second slide position, and a second cooperating mechanism is provided between the release lever and the pedal arm for turning the release lever from the release rotational position to the non-release rotational position when the pedal arm is turned from a parking brake engaging position to a parking brake disengaging position.
According to another aspect of the invention, a vehicular foot-operated parking brake control apparatus includes a mounting bracket adapted to be fixed to a vehicle body, a pedal arm rotatably mounted on the bracket for moving between a parking brake disengaging position and a parking brake engaging position, a plurality of ratchet teeth provided on the bracket, and a pawl rotatably mounted on the pedal arm for rotation between a first rotational position in which the pawl is engaged with one of the ratchet teeth and a second rotational position in which the pawl is disengaged from the ratchet teeth, with the pawl being mounted on the pedal arm by way of an elongated hole for slidably moving between a first slide position and a second slide position. A release lever is rotatably mounted on the pedal arm for rotating between a release rotational position and a non-release rotational position. A spring has a first end connected to the pawl and a second end connected to the release lever to urge the release lever towards the non-release rotational position while urging the pawl towards the first rotational position before the pedal arm is rotated from the parking brake disengaging position to the parking brake engaging position, and for urging the release lever towards the release rotational position and urging the pawl towards the second rotational position when the pedal arm is in the parking brake engaging position.